The 40-year-old former Dutch international defender, who had been in charge as caretaker since Martin Jol stepped down on 6 December, will be assisted by current No2 Danny Blind and Hennie Spijkerman, an arrival from Ajax Cape Town FC.

"I am very proud," said De Boer, a UEFA Cup and the UEFA Champions League winner with Ajax. "I think I always have stayed a real Ajax man. Even when I was abroad for a long period, I kept on following Ajax and always had a special place for this club in my heart.

"Five years ago, I came back to help Ajax further with youth development as youth coach and now I make the step to the first team. I only try to give everything in the best possible way for Ajax, as Ajax is the most important thing.

"I want to continue with what we started and work further on the details to improve us," added De Boer, who also assisted Bert van Marwijk at the 2010 FIFA World Cup where the Netherlands finished as runners-up.

Capped 112 times, De Boer continued his career with FC Barcelona, Rangers FC, Galatasaray AŞ and Al-Rayyan SC before joining Ajax as youth coach. His debut in his current role ended with a stunning 2-0 UEFA Champions League victory against AC Milan and follow-up successes in the league versus BV Vitesse and AZ Alkmaar in the Dutch Cup convinced the club to offer him the post permanently.

Ajax face RSC Anderlecht in the UEFA Europa League round of 32, with the first leg in Belgium on 17 February and the return the following week.

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